This invention relates to a chain incorporating a plurality of rolling bodies between a roller and a bushing, between the bushing and a pin, or between the roller and the pin.
Chains incorporating a plurality of metallic rolling bodies between a roller and a bushing, between the bushing and a pin, or between the roller and the pin, are well known. These chains required a lubricant, such as grease or the like, to prevent direct contact between the metallic rolling bodies. However, when the lubricant deteriorates or flows out, direct contact between the rolling bodies causes burning or the like, resulting in failure of the inner and outer plates to bend relative to each other, as required for proper operation of the chain. Thus, periodic replenishment of the lubricant was required.
To solve this problem, a chain incorporating a plurality of rolling bodies between a roller and a bushing has been provided, in which metallic rolling bodies and polyethylene resin rolling bodies were disposed in alternating arrangement, obviating the use of a lubricant such as grease or the like.
However, the chain incorporating alternating metallic and polyethylene resin rolling bodies exhibited two problems. First, since the polyethylene resin is heat-resistant only to a temperature of approximately 90xc2x0 C., it cannot be used in an environment where temperatures exceeding approximately 90xc2x0 C are encountered. Second, even when the chain is used at a moderate temperature, when the rate of revolution of the roller reaches about 185 rpm, frictional heat resulting from rotation of the roller causes the temperature of the rolling section to exceed the heat-resisting temperature of the polyethylene resin. As a result, the surface of the polyethylene resin rolling body is fused, and the rolling body cannot rotate smoothly.
Accordingly, a general object of this invention is to solve the aforementioned problems encountered in the use of conventional roller chains.
Another object of the invention is to provide a chain incorporating rolling bodies that can be used at a high temperature.
According to one aspect of the invention, a chain incorporates a plurality of rolling bodies between a roller and a bushing, and at least one of the plurality of rolling bodies is a carbon-impregnated ceramic rolling body.
According to another aspect of the invention, a chain incorporates a plurality of rolling bodies between a roller and a bushing, and at least one of the plurality of rolling bodies is a carbon-coated metallic rolling body.
According to another aspect of the invention, a chain incorporates a plurality of rolling bodies between a bushing and a pin, and at least one of the plurality of rolling bodies is a carbon-impregnated ceramic rolling body.
According to another aspect of the invention, a chain incorporates a plurality of rolling bodies between a bushing and a pin, and at least one of the plurality of rolling bodies is a carbon-coated metallic rolling body.
According to another aspect of the invention, a chain incorporates a plurality of rolling bodies between a roller and a pin, and at least one of the plurality of rolling bodies is a carbon-impregnated ceramic rolling body.
According to still another aspect of the invention, a chain incorporates a plurality of rolling bodies between a roller and a pin, and at least one of the plurality of rolling bodies is a carbon-coated metallic rolling body.
Thus, according to the invention, a carbon-impregnated ceramic, or carbon-coated metallic, rolling body is incorporated in a chain, between a roller and a bushing, between a bushing and a pin therein, or between a roller and a pin therein. The chain can be used at a high temperature by virtue of the self-lubricating properties of carbon at high temperature. Moreover, failure of the chain resulting from the generation of heat due to the rotation of the roller or bushing can be prevented, and therefore the chain can be adapted to high speed operation. Further, since no lubricant is required, the operating cost can be reduced, and cleaning of the chain is easier. Further, because carbon is chemically resistant, it is possible to use the chain in an acidic or alkaline environment.